H.W. Parke's Greek Oracles, first published in 1967, presents an illuminating introduction to a fascinating and often under-acknowledged aspect of the ancient world: its religion.

The Homeric epics have sometimes been regarded as the scriptures of antiquity. But to the Greeks who sought guidance in the troubles of their world, the normal method of ascertaining the will of God on some particular issue would not be to consult a book, but to enquire from a prophet. From the individual with a reputation for divination to a priesthood officially recognised by the state, the wide field of prophecy was dominated by its traditional oracular centres, pre-eminently Delphi.

Conclusions are based on a detailed examination of this latter oracle throughout the thousand years when the religious culture of the Graeco-Roman world was oriented towards prophecy - an orientation which persevered until a new religion, with novel access to God, superseded it.